The present invention relates generally to railroad right-of-way maintenance machinery, and specifically to machinery used for applying anchors to rail ties for securing rail tie plates and rails to the ties.
A railway anchor clamps onto a rail, and is positioned to abut the tie and the tie plate, to resist the movement of the rail relative to the tie. Railway anchors as contemplated herein include different configurations and models of anchors, such as spring-type or drive-on anchors made by different manufacturers, or any other rail fasteners positioned adjacent tie plates and used for retaining tie plates upon the ties, as are known to those skilled in the art.
During the course of railroad maintenance work, it is common that existing rail anchors are removed during the replacement of rail ties, tie plates, rails and for other maintenance operations. Once the desired maintenance is complete, the anchors need to be reinstalled. Alternatively, the anchors themselves can fail and new anchors need to be installed in their place.
Railroad maintenance machines typically include a frame which is either self-propelled or towable along the track, and a workhead configured to perform the maintenance task. Such devices typically have a travel position, where the portion of the workhead is held sufficiently above the track to avoid damage by obstacles including the track itself, and a work position. During operation in the work position, the units typically move between a loading position for loading the repair part, and a track engaging position for applying the repair part. To avoid damage to the mechanisms, such units are designed for operation so that either travel is prohibited when these mechanisms are in the latter two positions, or the mechanisms automatically rise to the travel position when the unit begins to move to the next location.
While protecting the rail anchor applicator mechanisms, these conventional operational precautions tend to take time and limit productivity of the anchor application process. Further, in cases where the anchor applicator is one of a chain of maintenance machines, the productivity of the overall maintenance of the railroad is limited as measured by the rate of the slowest unit.
Further, in some prior art apparatuses for securing anchors onto rails, manual positioning of the anchors adjacent the rail is required before engagement onto the rail by the apparatus. This requires an additional person to place the anchor adjacent the rail, or requires the operator to perform two tasks: placement and application. In other prior art apparatuses, such as the apparatus disclosed by Freymuth et al., U.S. Pat. No. 5,142,987, anchors are continuously transported by a delivery mechanism. These known delivery mechanisms are unnecessarily complex and include multiple moving parts such as drive chains, pulleys, hydraulic motors, among other components.
Thus, there is a need for an improved rail anchor applicator which enables a high frequency of anchor applications while protecting the anchor applicator mechanisms.
There is also a need for an improved rail anchor applicator which is configured to continuously deliver anchors with minimal moving parts.